Observations from growers fields at the central coast of California showed that strawberry (Fragaria X ananassa Duchesne) plants from fields drip-fumigated with chloropicrin (CP) or InLine revealed reduced yields at later growth stages compared to methyl bromide and CP (MeBr + CP) fumigated fields. A field experiment was conducted to evaluate the effect of different fumigants (CP and MeBr + CP), planting times (9 or 4 weeks past fumigation), and N fertilization rates (1x standard rate, 2x standard rate) on N mineralization dynamics over the strawberry growing season. Net N mineralization and nitrification rates were determined on a monthly basis from August 2004 to September 2005 by a combined ion exchange resin technique (PRS^TM anion probes) and soil extraction method (1 M KCl extract). PRS^TM anion probes were buried at 0-15 and 15-30 cm depth at the center and edge of raised beds to monitor available NO₃-N in the soil. Soil samples were collected at the same depths and bed locations. Net N mineralization and nitrification rates, growth parameters, fruit yields and quality (fruit weight and firmness) data over a single growing season will be presented. The results of this study are expected to answer the question whether higher strawberry yields in MeBr + CP fumigated soils relative to CP treated soils are related to the efficacy of the fumigants, to planting time, or to N availability.